1. Field of the Invention
The present invention relates to an infrared detector, more particularly, it relates to a structure of a cold shield for infrared detector arrays.
2. Description of the Related Art
Infrared images are detected by a infrared detector of an imaging system. The infrared detector comprises an infrared detector array and an infrared shielding device, which absorbs infrared radiation and is fully cooled so that the shielding device does not become an infrared emitting source. Since the infrared shielding device is cooled, it is known as a cold shield.
The cold shield excludes unnecessary and undesired infrared radiation, and necessary and desired infrared radiation to be detected is allowed to pass through the cold shield, whereby the infrared images to be detected are accurately detected by the detector array. Conventionally, however, the infrared radiation reflected by an electrode on the detector element in an array is reflected by optical parts and then sometimes impinges to the detective area. Thus the detecting accuracy for the infrared radiation was lowered. This phenomenon is known as optical crosstalk.